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Definition of an optimal consumption strategy for the public transport system of the city of Barcelona within the framework of the E-MED project
No full textThis study aims to identify whether the topography of the route a bus follows can affect the optimal technology for it. For this purpose, two routes from the city of Barcelona with contrasting characteristics have been analysed: one with significant elevation (V13) and another with an almost flat profile (H10). To achieve this, a MATLAB-based longitudinal bus dynamics simulator has been developed and validated, which estimates the energy consumption of different powertrain technologies, including diesel, compressed natural gas (CNG), electric buses with night charging and opportunity charging (BEB-OVC and BEB-OP, respectively), non-plug-in hybrids and hydrogen fuel cell buses, based on real data from urban routes with various topographies, recorded via GPS. The model has been validated with realworld data provided from the same routes, demonstrating high accuracy, with errors below 5%. The results show that topography significantly influences energy consumption, with increases of 35% to 46% on routes with greater gradients. Diesel and CNG buses have the highest consumption on both routes, while hybrids reduce consumption by 21%, and electric and hydrogen buses have considerably lower consumption, up to 85% and 60% less than diesel respectively. In the economic analysis, CNG buses and electric buses with opportunity charging are found to be the most cost-competitive options in total cost per kilometre, followed by diesel, electric buses with night charging and hybrids. Fuel cell buses are less economically viable. Topography does not alter the order of preference but can reduce the cost difference between gas and electric buses with opportunity charging on more demanding routes. Sensitivity analysis indicates that small changes in personnel or acquisition costs, as low as 5%, can change the preferred technology to BEB-OP. Furthermore, variations in the price of CNG, affected by geopolitical factors, could make BEBs more advantageous. The potential future reductions in BEB costs and public subsidies could reinforce this trend. To conclude, the developed methodology offers a tool for transport authorities to select the most appropriate bus technology according to their route characteristics, cost trends and environmental priorities, considering the uncertainty of energy markets
Modelització de l'expansió de les taques marrons del plàtan
No full textThis work aims to understand and model the process of formation and expansion of brown spots in banana skin (Musa spp.) after its commercialization. Although browning has been studied on a physiological scale, its quantification and numerical representation remains a challenge. To address this problem, six bananas were acquired from the same hand and subjected to different environmental conditions (coating with plastic film, cooling and variation in the proximity between fruits), recording different parameters through an environmental sensor. At the same time, a mathematical model of reaction-diffusion type was developed, implemented in MATLAB software, to simulate the diffusion of oxygen in banana tissue and the formation of browning associated with enzyme activity. The results show a good agreement between experimental observations and simulations, reproducing phenomena such as the bistable behavior, the influence of oxygen availability, the limited number of spots and the effect of temperature on the speed of the process. In addition, it has been possible to quantify the density and evolution of the spots over time. In summary, this study proposes an integrated approach to describe the browning of bananas, with potential applications in the agri-food field to improve the conservation and useful life of the product.Aquest treball té com a objectiu comprendre i modelar el procés de formació i expansió de les taques marrons a la pell del plàtan (Musa spp.) després de la seva comercialització. Tot i que el bruniment ha estat estudiat a escala fisiològica, la seva quantificació i representació numèrica continua essent un repte. Per abordar aquesta problemàtica, es van adquirir sis plàtans d'una mateixa mà i es van sotmetre a diferents condicions ambientals (recobriment amb film plàstic, refrigeració i variació en la proximitat entre fruits), registrant diferents paràmetres mitjançant un sensor ambiental. Paral·lelament, es va desenvolupar un model matemàtic de tipus reacció-difusió, implementat al programari MATLAB, per simular la difusió de l'oxigen en el teixit del plàtan i la formació de bruniment associada a l'activitat enzimàtica. Els resultats mostren una bona concordança entre les observacions experimentals i simulacions, reproduint fenòmens com la biestabilitat del bruniment, la influència de la disponibilitat d'oxigen, el nombre limitat de taques i l'efecte de la temperatura sobre la velocitat del procés. A més, s'ha pogut quantificar la densitat i l'evolució de les taques al llarg del temps. En resum, aquest estudi proposa una aproximació integrada per descriure el bruniment del plàtan, amb aplicacions potencials en l'àmbit agroalimentari per millorar la conservació i la vida útil del producte.Este trabajo tiene como objetivo comprender y modelar el proceso de formación y expansión de las manchas marrones a la piel del plátano (Musa spp.) después de su comercialización. A pesar de que el pardeamiento enzimático ha sido estudiado a escala fisiológica, su cuantificación y representación numérica continúa siendo un reto. Para abordar esta problemática, se adquirieron seis plátanos de una misma mano y se sometieron a diferentes condiciones ambientales (recubrimiento con film plástico, refrigeración y variación en la proximidad entre frutos), registrando diferentes parámetros mediante un sensor ambiental. Paralelamente, se desarrolló un modelo matemático de tipo reacción-difusión, implementado en el software MATLAB, para simular la difusión del oxígeno en el tejido del plátano y la formación de pardeamiento asociada a la actividad enzimática. Los resultados muestran una buena concordancia entre las observaciones experimentales y simulaciones, reproduciendo fenómenos como la biestabilidad del pardeamiento, la influencia de la disponibilidad de oxígeno, el número limitado de manchas y el efecto de la temperatura sobre la velocidad del proceso. Además, se ha podido cuantificar la densidad y la evolución de las manchas a lo largo del tiempo. En resumen, este estudio propone una aproximación integrada para describir el pardeamiento del plátano, con aplicaciones potenciales en el ámbito agroalimentario para mejorar la conservación y la vida útil del producto.Objectius de Desenvolupament Sostenible::9 - Indústria, Innovació i InfraestructuraObjectius de Desenvolupament Sostenible::12 - Producció i Consum Responsable
Estudio de viabilidad de producción de aceite de oliva en el Valle Chicama - Perú
No full textL’objectiu d’aquest treball és la investigació de la viabilitat de la implementació d’una planta d’oli d’oliva a la zona agrícola del Valle Chicama, situat a la costa nord del Perú. Mitjançant un cultiu intensiu de la varietat Arbequina, el projecte cerca l’objectiu de poder predir si és viable cultivar i posteriorment produir oli d’oliva a la zona, tenint com a base un terreny de 7,5 hectàrees en una localització que compleix amb la majoria de les característiques necessàries per al cultiu d’aquest producte.
El disseny d’una planta moderna inclou maquinària especialitzada per tal de garantir un producte d’alta qualitat, amb un sistema de reg tecnificat per degoteig. L’anàlisi de mercat ens marca el camí cap a un negoci que creix any rere any. A més de ser rendible, el projecte generarà ocupació local i promourà el consum de productes més saludables.Este trabajo tiene como objetivo la investigación de viabilidad de la implementación de una planta de aceite de oliva en la zona agrícola del Valle Chicama, ubicada en la costa norte del Perú. Realizando un cultivo intensivo de la variedad Arbequina, el proyecto busca el objetivo de poder predecir si es viable cultivar y posteriormente producir aceite de oliva en la zona, teniendo como base un terreno de 7.5 hectáreas en una localización que cumple con la mayoría de las características que necesita el cultivo de este producto. El diseño de una planta moderna incluye maquinaria especializada así garantizar un producto de alta calidad, con un riego tecnificado por goteo. El análisis de mercado nos marca la ruta hacia un negocio que incrementa años tras año. Además de ser rentable, el proyecto generará empleo local y promoverá el consumo de bienes mas saludables.This project aims to study the feasibility of setting up an olive oil production plant in the agricultural area of the Chicama Valley, located on the northern coast of Peru. By carrying out intensive cultivation of the Arbequina variety, the project seeks to determine whether it is viable to grow and later produce olive oil in the area, using a 7.5-hectare plot that meets most of the conditions needed for this crop. The design of a modern plant includes specialized machinery to ensure a high-quality product, along with a drip irrigation system. Market analysis shows that this is a business that grows year by year. In addition to being profitable, the project will generate local jobs and promote the consumption of healthier products
Low-cost digital-twin VR teleoperation of a 3D-printed robotic arm for STEM education
No full textThe integration of Virtual Reality (VR) with robotic systems offers opportunities for enhancing STEM (Science, Technology, Engineering, and Mathematics) education. This paper presents the design, implementation, and evaluation of a low-cost teleoperation system for a 3D-printed robotic arm, specifically tailored for educational applications. The system uniquely combines VR for intuitive control, a real-time digital twin for system visualization and understanding, and accessible open-source hardware. Utilizing a Meta Quest 2 headset, the Unity 3D engine, an Arduino MEGA 2560-based InMoov robotic arm, and a wireless communication architecture via an ESP32 module and UDP/IP, we demonstrate that this platform can be used for educational purposes. Experimental results validate the system’s effectiveness in providing an engaging, hands-on platform for students to explore concepts in robotics, programming, kinematics, and cyber-physical systems with an average operational latency of ~700 ms. The complete robotic arm materials—excluding the assembly—can be reproduced for under €400, greatly lowering the barrier for adoption in resource-constrained classrooms. This work underscores the potential of affordable VRrobotic digital twin systems to democratize access to advanced technological learning experiences in STEM.Peer ReviewedPostprint (author's final draft
Development of a safety analysis FMEA tool for OSO#05 compliance for low level of robustness operations
No full textThe rise in UAS operations requires constant updates to the regulatory framework to support safe operations. In response, EASA and international standardization bodies have been publishing new standards and Means of Compliance (MoCs) that provide applicants with practical ways to demonstrate conformity with regulatory requirements. Currently, UAS operations classified under the Specific category are characterized by higher operational complexity or risk than those in the Open category. These operations usually require an operational risk assessment and formal authorization from the competent authority. Compliance is typically demonstrated using the SORA methodology, which maps the identified operational risks to specific Operational Safety Objectives (OSOs). An OSO is a specific safety requirement or goal that shall be met to reduce the operation's risk to an acceptable level. However, despite the publication of MoCs and standards, applicants often face practical challenges regarding OSOs compliance. Existing documents are structured too broadly and do not provide clear guidance on how to start or proceed with the analysis. This project has taken the specific example of OSO#05, which requires that the UAS be designed with adequate system safety and reliability. The MoC for OSO#05, already published for SAIL III operations, recommends conducting a Functional Hazard Analysis (FHA) and a Failure Mode and Effect Analysis (FMEA) to perform a UAS system safety analysis. What is provided, hence, are recommendations rather than step-by-step instructions. In many cases, this may leave applicants uncertain about how to translate the required high-level requirements into specific and documented assessments. To address this, the project provides a two-part solution. For starters, an Excel-based FHA and FMEA framework that applicants can directly use to structure their safety assessment has been developed. Secondly, a prototype Python tool connected to a regulatory database, which automatically retrieves relevant standards content and guidance for specific FMEA fields has been created. The database, implemented in SQLite with FTS5, segments documents into hierarchical sections and enables fast retrieval of relevant information. It should be highlighted that this project has been carried out in collaboration with Applus+ Laboratories, which provided real-world context to ensure the developed framework aligned with industry practices. The approach allowed defining a clear FHA and FMEA structure and building a structured database with properly organized content. Additionally, FTS5 demonstrated fast retrieval when matches were found. Nevertheless, the main limitation has been the construction of queries to obtain accurate results. Therefore, looking ahead, instead of performing literal text searches and focusing on improving query robustness, techniques that can capture the contextual meaning of words could be explored. Overall, the outcome is not a deployable product. It shall be treated as a methodology and a prototype aimed at reducing ambiguity, providing structured evidence for compliance, and establishing a scalable foundation for systematic UAS safety analysis.7 - Energia Assequible i No Contaminant13 - Acció per al Clim
Exploration of drawing conventions in cartography
No full textLa tesi pretén explorar les convencions inherents al dibuix i la cartografia, i el seu paper en els mètodes, les tècniques i les idees que dicten la representació del material visual de l'autor a l'observador. Les convencions del dibuix, com totes les convencions, són inherentment culturals en origen i trets, i el temps i la cultura són dos factors que creen una gran varietat en la representació visual del mateix material. Els objectius principals són identificar les relacions entre les convencions del dibuix passades i contemporànies en les disciplines de la cartografia i l'urbanisme, i explorar combinacions de convencions que produeixin dibuixos rics i variats que abordin tant els costats objectius com subjectius de la representació. L'enfocament d'aquest estudi se centra a Catalunya, la península Ibèrica i les regions de la Mediterrània, que van formar la base geogràfica de la recerca de postgrau de l'autor.
La tesi es presenta en dues parts: una col·lecció de convencions cartogràfiques observades en mapes principalment de la regió mediterrània, i una sèrie de dibuixos personals de l'autor de la tesi anomenats el diari de dibuix. Tot i que aquestes dues parts es van dur a terme simultàniament, es presenten com a parts separades a la tesi.La tesis pretende explorar las convenciones inherentes al dibujo y la cartografía, y su papel en los métodos, técnicas e ideas que determinan la representación del material visual desde el autor hasta el observador. Las convenciones de dibujo, como todas las convenciones, tienen un origen y rasgos inherentemente culturales, y el tiempo y la cultura son dos factores que crean una gran variedad en la representación visual del mismo material. Los objetivos principales son identificar las relaciones entre las convenciones de dibujo pasadas y contemporáneas en las disciplinas de la cartografía y el urbanismo, y explorar combinaciones de convenciones que produzcan dibujos ricos y variados que aborden tanto los aspectos objetivos como subjetivos de la representación. El estudio se centra en Cataluña, la Península Ibérica y las regiones del Mediterráneo, que constituyeron la base geográfica de la investigación de posgrado del autor.
La tesis se presenta en dos partes: una recopilación de convenciones cartográficas encontradas en mapas principalmente de la región mediterránea, y una serie de dibujos personales del autor, conocida como el diario de dibujo. Si bien estas dos partes se desarrollaron simultáneamente, se presentan como partes separadas en la tesis.The thesis intends to explore the conventions inherent in drawing and cartography, and their role in the methods, techniques, and ideas that dictate the representation of visual material from author to observer. Drawing conventions, as with all conventions, are inherently cultural in origin and traits, and time and culture are two factors that create a vast variety in visual representation of the same material. The primary objectives are to identify the relationships between past and contemporary drawing conventions in the disciplines of cartography and urbanism, and explore combinations of conventions that produce rich and varied drawings engaging with both the objective and subjective sides of representation. The focus of this study centers on Catalunya, the Iberian Peninsula, and regions of the Mediterranean, which formed the geographic basis of the author’s graduate research.
The thesis is presented in two parts: a collection of found cartographic conventions observed in maps primarily from the Mediterranean region, and series of personal drawings by the author of the thesis referred to as the drawing diary. While these two parts were pursued simultaneously, they are presented as separate parts in the thesis.Award-winnin
Data–driven nonlinear finite element modelling of stub recycled aggregate concrete-filled steel tube columns under axial compression
No full textRecycled aggregate concrete–filled steel tubes are composite structural members consisting of steel tubes filled with recycled aggregate concrete produced from crushed construction and demolition waste. The steel tube confinement enhances the mechanical performance of the concrete, increasing load–bearing capacity and ductility under axial compression. While experimental research on these sustainable members is growing, high–fidelity 3D numerical models capable of accurately predicting their behaviour remain limited. This paper presents an advanced framework for simulating the axial response of this type of structural member. The workflow integrates Bayesian optimisation algorithm with a 3D nonlinear finite element model available in commercial software, automated via Python scripting. A dataset of 209 experimental specimens is used to calibrate a constitutive model for confined recycled concrete, essential for reliable column analysis. The proposed model extends the Eurocode 2 stress–strain relationship in compression to capture the specific behaviour of confined recycled aggregate concrete. Validation against experimental results shows good agreement in load–displacement response and ultimate strength prediction. Derived from a wide experimental dataset, the modelling strategy enables rapid and reliable assessment of column performance. Beyond its application to this column type, the proposed framework illustrates the broader potential of integrating simulation, optimisation, and data–driven modelling, offering a transferable methodology for diverse structural problems.The first and the last authors thank the Ministry of Science, Technological Development and Innovation, Republic of Serbia, for financial support through the project number 200092. The second author thanks the Universitat Politècnica de Catalunya for financial support through the grant number 2024-PROD-00090. Any opinions, findings, conclusions, and/or recommendations in the paper are those of the authors and do not necessarily represent the views of the individuals or organisations acknowledged.
The authors acknowledge the use of Free vector icons from Flaticon (www.flaticon.com).Peer ReviewedPostprint (published version
Creació d’un model de negoci - marketplace de lloguer d’art
No full textAquest treball de final de màster té com a objectiu el disseny i desenvolupament d’un model de negoci per a un marketplace de lloguer de quadres, amb la finalitat de democratitzar l’accés a l’art i oferir noves oportunitats de visibilitat i rendibilitat als artistes. El projecte neix de la detecció d’un problema recurrent en el sector: la dificultat dels creadors per donar sortida a les seves obres i la falta d’alternatives per part dels consumidors a l’hora de gaudir d’art en espais quotidians. La memòria s’estructura en diferents apartats que inclouen una introducció teòrica al sector i als seus antecedents, un anàlisi de mercat per identificar oportunitats i competència, el desenvolupament del model de negoci i la seva estratègia de màrqueting, així com un estudi econòmic detallat per avaluar-ne la viabilitat. A través d’aquest enfocament integral, el treball busca aportar una proposta innovadora que combini la dimensió cultural i econòmica de l’art amb les noves tendències de consum digita